Develop Reference

Subsequence words

Suppose this is my .txt file ABCDBCD and I want to use .substring to get this:
ABC BCD CDB DBC BCD
How can I achieve this? I also need to stop the program if a line is shorter than 3 characters.
static void lesFil(String fil, subsekvens allHashMapSubsequences) throws FileNotFoundException{
Scanner scanner = new Scanner(new File("File1.txt"));
String currentLine, subString;
while(scanner.hasNextLine()){
currentLine = scanner.nextLine();
currentLine = currentLine.trim();
for (int i = 0; i + subSize <= currentLine.length(); i++){
subString = currentLinje.substring(i, i + subSize);
subSekStr.putIfAbsent(subString, new subsequence(subString));
}
}
scanner.close();

With a minor changes of your code:
public static void main(String[] args) throws FileNotFoundException {
Scanner scanner = new Scanner(new File("C:\\Users\\Public\\File1.txt"));
String currentLine, subString;
int subSize = 3;
while (scanner.hasNextLine()) {
currentLine = scanner.nextLine();
currentLine = currentLine.trim();
if (currentLine.length() < subSize) {
break;
}
for (int i = 0; i + subSize <= currentLine.length(); i++) {
subString = currentLine.substring(i, i + subSize);
System.out.print(subString + " ");
}
System.out.print("\n");
}
scanner.close();
}

This may be what you need
String str = "ABCDBCD";
int substringSize = 3;
String substring;
for(int i=0; i<str.length()-substringSize+1; i++){
substring = str.substring(i, i+substringSize);
System.out.println(substring);
}

import java.util.*;
public class Main
{
public static void main(String[] args) {
String input = "ABCDBCD";
for(int i = 0 ; i < input.length() ; i++) {
if(i < input.length() - 2) {
String temp = input.substring(i,i+3);
System.out.println(temp);
}
}
}
}

Manipulating strings and integers via two dimensional array from an external file java

I am trying to design a program that takes data from an external file, stores the variable to arrays and then allows for manipulation.sample input:
String1 intA1 intA2
String2 intB1 intB2
String3 intC1 intC2
String4 intD1 intD2
String5 intE1 intE2
I want to be able to take these values from the array and manipulate them as follows;
For each string I want to be able to take StringX and computing((intX1+
intX2)/)
And for each int column I want to be able to do for example (intA1 + intB1 + intC1 + intD1 + intE1)
This is what I have so far, any tips?
**please note java naming conventions have not been taught in my course yet.
public class 2D_Array {
public static void inputstream(){
File file = new File("data.txt");
try (FileInputStream fis = new FileInputStream(file)) {
int content;
while ((content = fis.read()) != -1) {
readLines("data.txt");
FivebyThree();
System.out.print((char) content);
}
} catch (IOException e) {
e.printStackTrace();
}
}
public static int FivebyThree() throws IOException {
Scanner sc = new Scanner(new File("data.txt"));
int[] arr = new int[10];
while(sc.hasNextLine()) {
String line[] = sc.nextLine().split("\\s");
int ele = Integer.parseInt(line[1]);
int index = Integer.parseInt(line[0]);
arr[index] = ele;
}
int sum = 0;
for(int i = 0; i<arr.length; i++) {
sum += arr[i];
System.out.print(arr[i] + "\t");
}
System.out.println("\nSum : " + sum);
return sum;
}
public static String[] readLines(String filename) throws IOException {
FileReader fileReader = new FileReader(filename);
BufferedReader bufferedReader = new BufferedReader(fileReader);
List<String> lines = new ArrayList<String>();
String line = null;
while ((line = bufferedReader.readLine()) != null)
{
lines.add(line);
}
return lines.toArray(new String[lines.size()]);
}
/* int[][] FivebyThree = new int[5][3];
int row, col;
for (row =0; row < 5; row++) {
for(col = 0; col < 3; col++) {
System.out.printf( "%7d", FivebyThree[row][col]);
}
System.out.println();*/
public static void main(String[] args)throws IOException {
inputstream();
}
}

I see that you read data.txt twice and do not use first read result at all. I do not understand, what you want to do with String, but having two-dimension array and calculate sum of columns of int is very easy:
public class Array_2D {
static final class Item {
final String str;
final int val1;
final int val2;
Item(String str, int val1, int val2) {
this.str = str;
this.val1 = val1;
this.val2 = val2;
}
}
private static List<Item> readFile(Reader reader) throws IOException {
try (BufferedReader in = new BufferedReader(reader)) {
List<Item> content = new ArrayList<>();
String str;
while ((str = in.readLine()) != null) {
String[] parts = str.split(" ");
content.add(new Item(parts[0], Integer.parseInt(parts[1]), Integer.parseInt(parts[2])));
}
return content;
}
}
private static void FivebyThree(List<Item> content) {
StringBuilder buf = new StringBuilder();
int sum1 = 0;
int sum2 = 0;
for (Item item : content) {
// TODO do what you want with item.str
sum1 += item.val1;
sum2 += item.val2;
}
System.out.println("str: " + buf);
System.out.println("sum1: " + sum1);
System.out.println("sum2: " + sum2);
}
public static void main(String[] args) throws IOException {
List<Item> content = readFile(new InputStreamReader(Array_2D.class.getResourceAsStream("data.txt")));
FivebyThree(content);
}
}

Reading a CSV in Java / Jython

Here's a simple problem:
public static double[] stringsToDoubles(String[] inputArr) {
double[] nums = new double[inputArr.length];
for (int i = 0; i < nums.length; i++) {
nums[i] = Double.parseDouble(inputArr[i]);
}
return nums;
}
public static double[][] readPointCloudFile(String filename, int n) {
double[][] points = new double[n][];
String delimiter = ",";
Scanner sc = new Scanner(filename);
for (int i = 0; i < n; i++) {
String line = sc.nextLine();
points[i] = stringsToDoubles(line.split(delimiter));
}
return points;
}
from jython I import properly, and then call the function as
readPointCloudFile("points.txt", 3)
This gives the error
java.lang.NumberFormatException: java.lang.NumberFormatException: For input string: "points.txt"

You never read from the file. You pass the file name to the Scanner and assume that this string is your csv data, but it is just the filename.
Reading a file can be done as follows when you use Java 8:
import java.nio.file.Files;
import java.nio.file.Paths;
[...]
public static double[][] readPointCloudFile(String filename, int n) {
double[][] points = new double[n][];
String delimiter = ",";
String filecontent = new String(Files.readAllBytes(Paths.get(filename)));
Scanner sc = new Scanner(filecontent);
for (int i = 0; i < n; i++) {
String line = sc.nextLine();
points[i] = stringsToDoubles(line.split(delimiter));
}
return points;
}

Here's my solution in the spirit of solving your own problems, but I'll give someone else credit because the other solutions are probably better.
public static double[] stringsToDoubles(String[] inputArr){
double[] nums = new double[inputArr.length];
for(int i = 0; i < nums.length; i++){
nums[i] = Double.parseDouble(inputArr[i]);
}
return nums;
}
public static double[][] readPointCloudFile(String filename, int n) throws FileNotFoundException{
double[][] points = new double[n][];
String delimiter = ",";
try{
Scanner sc = new Scanner(new File(filename));
for(int i = 0; i < n; i++){
String line = sc.nextLine();
points[i] = stringsToDoubles(line.split(delimiter));
}
} catch (FileNotFoundException e){
System.err.println(e.getMessage());
} finally {
return points;
}
}

match a string in file java

I have a problem. I need to use the first row of the txt as my string and then look in the same txt the occurrences and print the number, but I have a problem, for example; if my txt is like: wordwordword and my string is word, it only counts the first word, it does´t print the counter: 3, print the counter: 1. How can I solve this?
Demo.java
import java.io.*;
import java.util.*;
public class Demo {
public static void main(String args[]) throws java.io.IOException {
BufferedReader in = new BufferedReader(new FileReader("c.txt"));
Scanner sc = new Scanner(System.in);
String s1;
s1 = in.readLine();
String Word;
Word = s1;
String line = in.readLine();
int count = 0;
String s[];
do {
s = line.split(" ");
for (int i = 0; i < s.length; i++) {
String a = s[i];
if (a.contains(Word))
count++;
}
line = in.readLine();
} while (line != null);
System.out.println("first line: " + s1);
System.out.print("There are " + count + " occurences of " + Word
+ " in ");
java.io.File file = new java.io.File("c.txt");
Scanner input = new Scanner(file);
while (input.hasNext()) {
String word = input.nextLine();
System.out.print(word);
}
}
}
txt:
GAGCATAGA
CGAGAGCATATAGGAGCATATCTTGAGCATACCGAGCATATGAGCATAATATACCCGTCCGAGAGCATACACTGAGCATAAAGGAGCATAGAGCATACAACTGAGAATGGAGCATAGAGCATACGGAGCATAAGAGCATAGAGCATAGAGCATACGGAGCATAGAGCATAGAGCATAGCCGATGGGGAGCATACTGTTACGTAGAGCATACGAGCATAGCGCAAGAGCATAAAGAGCATAGAGCATATGAGCATATAGAGCATACGAGCATACAAGATCCGGGGAGCATAGCGAGGTAATAGTCGGAGCATAGAGCATAGAGCATATGAGCATACGGGAGCATAAATGAGCATAAGGAGCATAGAGCATAGAGCATAAGAGCATATCTCGAGCATAAGCGAGCATAGAGCATAAAAATCAATCACGTTGAGCATATGAGCATAAATACTGGAGCATAGATCGAGCATAGTAGAGCATACGAGCATAGAGCATAGGAGCATAAGAGCATATGAGCATATTGAGCATATGAAGGAGCATAAAAATGAGCATAAGGAGCATACCATCGTTGAGCATAATCCGAGCATAGGAGCATAGAATAGAGCATAGACAGGAGTTTTTGGAGCATATGAGCATAGAGCATAGAGCATAGAGCATAGAGCATAGAGCATAGAGCATATTCGAGCATAATTGAGCATATGAGCATAGAGCATATGGAGCATAGGCTGAGCATACCGAGCATAGCAATTAGAGCATAATCCTAGGGAGCATAGGAGCATACGTGAGCATAGCTGAGCATAGAGCATAGAGCATAGTGTTCGAGCATAGAGCATAGAGCATATGAGCATAGAGCATACTTGAGCATATGGTACGAGCATAGGAGCATATAAGGAGGAGCATATCGAGCATAGAGCATAGGCCTGGCCAGAGCATATAACCGAGCATAGGGTTGGAGCATAAGGCCGGAGCATACGAGCATACGAGCATATGAAATGAGCATAATGTGAGCATAGAGCATATCGAGCATATGAGCATAGGAGCATA
in this example with the txt, the program should print the counter= 21

import java.io.File;
import java.io.IOException;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Match {
public static String TEXT_FILE_LOCATION="input.txt";
public static void main(String[] args) throws IOException {
Scanner in = new Scanner(new File(TEXT_FILE_LOCATION));
String stringToSearch=in.nextLine();
StringBuffer buffer=new StringBuffer();
for(;in.hasNext();){
buffer.append(in.next());
}
Pattern pattern = Pattern.compile(stringToSearch);
Matcher matcher = pattern.matcher(buffer.toString());
int from = 0;
int count = 0;
while(matcher.find(from)) {
count++;
from = matcher.start() + 1;
}
System.out.println("Number of matches : "+count);
}
}

You can do it by looping through your text then match the string with part of the text.
Here it is:
public static void main(String[] args) {
String word = "word";
String text = "wordwordword";
int count = 0;
for(int i =0 ; i <text.length() ; i++){
for(int j = 0 ; j < word.length();j++){
if((j+i)>=text.length())break;
if(word.charAt(j)!=text.charAt(j+i))break;
if(j==word.length()-1)count++;
}
}
System.out.println(count);//prints 3
}
Also you could use .toCharArray() to get the characters in the string before looping to enhance the performance.
Here is the modified code for that :
public static void main(String[] args) {
char[] word = "word".toCharArray();
char[] text = "wordwordword".toCharArray();
int count = 0;
for(int i =0 ; i <text.length ; i++){
for(int j = 0 ; j < word.length;j++){
if((j+i)>=text.length)break;
if(word[j]!=text[j+i])break;
if(j==word.length-1)count++;
}
}
System.out.println(count);
}

Java - substring issues

I'm going to show all of my code here so you guys get a gist of what I'm doing.
import java.io.*;
import java.util.*;
public class Plagiarism {
public static void main(String[] args) {
Plagiarism myPlag = new Plagiarism();
if (args.length == 0) {
System.out.println("Error: No files input");
}
else if (args.length > 0) {
try {
List<String> foo = new ArrayList<String>();
for (int i = 0; i < 2; i++) {
BufferedReader reader = new BufferedReader (new FileReader (args[i]));
foo = simplify(reader);
for (int j = 0; j < foo.size(); j++) {
System.out.print(foo.get(j));
}
}
int blockSize = Integer.valueOf(args[2]);
System.out.println(args[2]);
// String line = foo.toString();
List<String> list = new ArrayList<String>();
for (int k = 0; k < foo.size() - blockSize; k++) {
list.add(foo.toString().substring(k, k+blockSize));
}
System.out.println(list);
}
catch (Exception e) {
e.printStackTrace();
}
}
}
public static List<String> simplify(BufferedReader input) throws IOException {
String line = null;
List<String> myList = new ArrayList<String>();
while ((line = input.readLine()) != null) {
myList.add(line.replaceAll("[^a-zA-Z]","").toLowerCase());
}
return myList;
}
}
This is the code that is using substring.
int blockSize = Integer.valueOf(args[2]);
//"foo" is an ArrayList<String> which I have to convert toString() to use substring().
String line = foo.toString();
List<String> list = new ArrayList<String>();
for (int k = 0; k < line.length() - blockSize; k++) {
list.add(line.substring(k, k+blockSize));
}
System.out.println(list);
When I specify blockSize as 4 in cmd this is the result:
[[, a, , ab, abc ]
the text file (standardised using my other code) is this:
abcdzaabcdd
so the result should be this:
[abcd, bcdz, cdza, ] etc.
Any help?
Thanks in advance.

Here is code showing how to improve a little your code. Main change is returning simplified string from simplify method instead of List<String> of simplified lines, which after converting it to string returned String in form
[value0, value1, value2, ...]
Now code returns String in form value0value1value2.
Another change is lowering indentation lever by removing unnecessary else if statement and braking control flow with System.exit(0); (you can also use return; here).
class Plagiarism {
public static void main(String[] args) throws Exception {
//you are not using 'myPlag' anywhere, you can safely remove it
// Plagiarism myPlag = new Plagiarism();
if (args.length == 0) {
System.out.println("Error: No files input");
System.exit(0);
}
String foo = null;
for (int i = 0; i < 2; i++) {
BufferedReader reader = new BufferedReader(new FileReader(args[i]));
foo = simplify(reader);
System.out.println(foo);
}
int blockSize = Integer.valueOf(args[2]);
System.out.println(args[2]);
List<String> list = new ArrayList<String>();
for (int k = 0; k < foo.length() - blockSize; k++) {
list.add(foo.toString().substring(k, k + blockSize));
}
System.out.println(list);
}
public static String simplify(BufferedReader input)
throws IOException {
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = input.readLine()) != null) {
sb.append(line.replaceAll("[^a-zA-Z]", "").toLowerCase());
}
return sb.toString();
}
}